Crane bucket equipment

ABSTRACT

A holder with a capacity for two crane buckets holds one of these buckets for filling while the other is being emptied. On return of the emptied bucket to the holder a mechanism is equipped to detach the emptied bucket from the crane cable and to attach the filled bucket to the crane cable. The crane bucket is designed so that its weight operates hydraulic means for causing bottom opening and closing.

[ Dec. 10, 1974 CRANE BUCKET EQUIPMENT FOREIGN PATENTS OR APPLICATIONS[76] Inventors: Raymond O. Jobst, i476 Trotwood 864,849 4/1961 GreatBritain..........i............i 294/70 Ave., Mississauga; William A.Perry,

28 Lewin Cres., Ajax, Ontario, both of Canada Primary Examiner-Frank E.Werner [22] Filed: Nov. 7, 1973 ABSTRACT 1 7 5 .l. m a D n o ru 3 .w ln. 0. A s BU m t oh u m. D. A l. l 2

[ Division Of 178,005, P 7, 1971, A holder with a capacity for two cranebuckets holds one of these buckets for filling while the other is beingemptied. On return of the emptied bucket to the holder a mechanism isequipped to detach the emptied bucket from the crane cable and to attachthe filled bucket to the crane cable. The crane bucket is designed sothat its weight operates hydraulic means for causing bottom opening andclosing.

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sum 10F e "Wm v "IIIIll a PATENTEUUEEWW 3.853.346

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FIG. 13

FIGI14 PATENTEU DEC 1 (H974 SHEEI 8 [IF 6 FIG.15

CRANE BUCKET EQUIPMENT This application is a division of application SN178,005 filed Sept. 7, i971 and now US. Pat. No. 3,780,8 80.

Thisinvention relates to a holder for crane buckets of the type usuallyused in the supply of concrete to construction sites, wherein theinvention provides a holder for supporting a bucket which allows thelowering of an empty bucket by the crane cable for filling; and saidsupport means supports at an adjacent location, a bucket which has beenalready filled, and the invention provides automatic means fordisconnecting the crane cable from the bucket just lowered andconnecting the same crane cable to the filled bucket so that no time islost of the crane operators time through manual interchange of buckets.

In drawings which illustrate a preferred embodiment of the invention:

FIG. 1 shows a perspective illustrating the function of a holder inaccord with the invention;

FIG. 2 shows across-section of the cable-bucket connection;

FIG. 3 shows a side view, bucket connection;

FIG. 4 shows a cross-section along the lines 4-4 of FIG. 3;

FIG. 5 shows a top view of the cable-bucket connection and disconnectionmechanism at a different stage of the operating cycle from FIG. 1;

FIG. 6 shows a side view of this mechanism; FIG. 7 shows a section alongthe lines 7-7 of FIG.

partly in section, of the FIGS. 8 l1 show schematically the operation ofthe connect-disconnect means between the bucket and the crane cable;

FIG. 12 14 show the operation of the hydraulic circuit; and

FIG. 15 shows 'a chute for filling the bucket.

In the drawings the bucket support means is a frame work supportedplatform or table having twin apertures, each adapted to hold a cranebucket 10. Crane bucket 10 for use with the invention, resemblesconventional buckets, differing in particular in their crane cableattachment means, their means for achieving orientation about a verticalaxis. I

It is preferable if the bucket be specially designed for the developmentwith dumping or discharging automatically rather than manually and abucket so designed is illustrated in FIG. 3. The bucket is preferablydesigned to be a surface of revolution about its intended vertical axisand provided with a conical lower extent 12 and a cylindrical upperextent 14 having diametrically opposed rollers 15 on opposite sidesthereof exterior of the bucket and mounted on horizontal axes, and anarm 16 pivotally connected at '19 to the top of the bucket at one end bymeans hereafter described and having upper plate 19 defining a pair ofopenings being bucket locations and dimensioned to receive the conicaland lower cylindrical portions 12 and 14 therein but to support on theedges of an opening the outwardly extend ing flanges 22 of the bucket.The bucket support means defines a cylindrical wall 26 about theposition of each bucket resting as described in the bucket location, andon each such wall 26 is an upwardly facing sloping track 28, designed toform a track for rollers 15 which are located on diametrically opposedlocations on the outside of each wall of the bucket.

The track 28 is designed to ensure, that whateverorientation the bucketis dropped into the aperture, the two rollers follow diametricallyopposed sectors of the track until the rollers come to rest in theopposed depressions 29 therein. In the preferred embodiment of theinvention the track 28, comprises two portions,

each semi-circular in plan view and each meeting the 5-8, theorientation of the bucket 10, created by the sloping tracks 28 are suchthat the line joining the apertures in the ears-17 of one arm 14 areparallel to the aperture in the cars 17 of the other arm 14 so that acoupling means may in one sliding motion, insert a pin 31 for couplingthrough one set of ear 17 apertures, and withdraw the pin 31 forcoupling from the other set of ear l7 apertures. Pairs of supports (heresupports 30) on each side of the pivot 19 are designed to support thearms 14 at a desired height for such coupling (here equal heights) whenthe arms 14 are unsupported by a crane cable.

In the invention, a coupling bracket 35 replaces the crane hook as themeans for attachment to the bucket 10, thus as far as the invention isconcerned, the hook is not essential as the bracket may be attached tothe cable. However, since the hook will usually be present for otherpurposes it is, in the preferred embodiment, used as the coupling meansbetween the crane cable and the cable bracket. Thus the crane hook 37 ishooked through an aperture 39 in a bracket 35 designed to extendlongitudinally downwardly from the spaced ears 17 with aligned aperturesat the other, the

thereon with an aperture 38 in each end and the aperture 38 are spacedso that they may simultaneously align with the two pairs of apertures inthe respective bucket arms 14 when the bucket arms 14 are both restingon supports 30 as best shown in FIG. 5 and 10. Although details of theconnections of the bucket arms 14 will be discussed hereafter itshould'be here noted that the shank 40 to which the bucket arm isattached, is provided with a vertical slot 42 designed to allow thepivot point 19 of the bucket arm 14 to always move to a point whereinthe bucket arms are maintained aligned by the supports 30 regardless ofthe height of the shank 40. When the attitude of the bucket 10 and thecable is such that the cable coupling'bracket 3S hangs vertically thereare provided hanging downwardly from the bracket arcuate plates 44movable therewith on each side of the bracket said plates 44 beingshaped to be convex downwardly.

As shown in FIGS. 1 and 7, a pin 31 is provided dimensioned to beinserted through a pair of bucket arm ear 17 apertures and through theaperture 38 in the coupling link located therebetween. The pin 31 isarranged to project outwardly at each end beyond the bucket link earmembers and the outwardly projecting portions are provided withcircumferential grooves 46.

The bucket support means between the two apertures, is provided with aslide 48 which may be mechanically, electrically, hydraulically, orotherwise actuable by a micro-switch 50 which is located to be contactedby the cable bracket plates 44 at the' lowest point of lowering thecable and coupling means. The slide 48 is actuable to move between twolimiting positions on the bucket holder in a relative movement directionparallel to the lines along which a pin 31 would be longitudinallyinserted in aligned apertures. On the slide 48 are mounted, projectingfrom opposite sides, forks 52 which are shaped to have the inside edgesof spaced tines fit in one of the circumferential grooves 46 of a pin 31and hence to receive and support a pin 31 moved downwardly thereintowith the grooves receiving the tines so that the forks support the pin.The pins 31 outside of each of the grooves 46 are provided with taperingends to assist entrance of the pin 31 into the aligned apertures.

(Please note that the position of the pins and slide shown in FIGS. 5-7differs from that shown in FIG. 1, in that relative to FIG. 1, the slide48 has moved to the opposite position hence the pin 31 of FIG. 1 has, inFIG. 5 been inserted in linkage apertures and a pin 31 not shown in FIG.1, is shown in FIG. 5 as just withdrawn from linkage apertures.)Furthermore it will be noted that FIG. 1 of the drawings corresponds tothe position of the buckets in FIG. 8 of the schematics and 1 FIG. 10 ofthe schematics corresponds to the state of tion of'the pins 31 isreversed, and the pin 31 removed from the bucket arm 16 in FIG. 5 iscoupling the 'arm 16 to a cablelink 36, the pin 31 passing through abucket arm and a cable link 36 in FIG. 5 is withdrawn to uncouple thesemembers.

The movement from one limiting position to the other is, as previouslynoted, caused when one of the arcuate plates 44'of the crane cablebracket 35 strikes the micro-switch 50. A cylinder 53 which may bepneumatic or hydraulic, is shown to schematically represent theactuating means, which will move the slide 48 from one position to theother. Both micro-switch actuated control system and the power devicefor operating the slide 48 are omitted since these, in many forms andalternatives are available to those skilled in the art. The micro-switch50 will be connected to a control circuit arranged so that thedepression of the micro-switch 50 by the arcuate plate 44 causesmovement of the slide 50 to the opposite limiting position to the one itis in, but to remain in the states to which it has been switched (eventhough the micro-switch 48 remains depressed) until the micro-switch 48is again depressed by a succeeding lowering of the plate 44.

As shown, the inside edges of the fork 52 tines are adapted to ride inone of the grooves 46 and to suspend the pin 31 in this way but to allowthe withdrawal of the pin upwardly from the forks 52 and insertion ofthe pin downwardly into the forks. It will be noted that the downwardlyextending arcuate plates 44 on the cable coupling means is (when abucket is suspended from a cable so that the coupling link, as well asthe cable bracket 35, is vertical) received in the pin groove 46 to holdthe pin against longitudinal movement out of its coupling position allas shown in FIG. 1 and 2.

The operation of the bucket supporting part of the invention is asfollows: a bucket 10 presumably empty after dumping at another location,is attached to the cable and hanging straight downward therefrom, asshown in'FIGS. 1, 2, 8 with the cable bracket 35 vertical (as it is inmost situations) but with the cable link 36 and the bucket arm 16coupled thereto, also disposed vertically. The bucket 10 just described,is being lowered into one of the holder locations while in the otherholder location, there is a bucket filled from chute 41 (fillingmaterial not shown) resting in the holder with its bucket 10 couplinglink 16 resting directed toward the other bucket holding aperture. Acoupling pin 31 is contained in the forks 52 aligned with the aperturesin ears 17 corresponding to the filled bucket. As the crane attachedbucket is lowered into position into the empty opening, the track 28acting on rollers 15 of the just lowered bucket, acts to place thebucket in the desired orientation, and the crane operator will controlthe crane cable location, to ensure that the bucket coupling arm 16 andthe crane cable coupling link 36 fall toward the other bucket locationas the cable continues to be lowered. (See FIG. 9.) When the empty(i.e., just lowered) bucket coupling arm 16 reaches its lower-mostposition as'defined by a pair of supports 30, the crane link 36 rotatesuntil a horizontal position is reached as the crane operator continuesto lower the cable. When the crane cable link is horizontally disposed,the link aperture is aligned with the f lled bucket arm 16 car aperture.Also as the bucket arm and link 36 move toward an orientationperpendicular to the bracket 35, the arcuate plates 44 move out of thegrooves 46 in the pin 31 (of the just-lowered and empty bucket) in whichthey have been riding to allow later removal of the pin 31. This pin 31comes to rest in the fork, which is located at one limiting position,receiving in its grooves'46 the inside edges of tines of the fork 52 sothat the fork 52 will withdraw the pin 31 when the fork 52 is moved bythe slide 48 to the other limiting position. When the cable coupling'link 36 and the bucket arm 16 are horizontal the still downwardlyextending arcuate plates 44 strike a micro-switch 50 actuating the slide48 actuating mechanism by means, not shown but well known to thoseskilled in the art, and movement of the slide causes the fork 52 towithdraw the pin 31 linking the empty and just lowered bucket from itsconnection with one end of the cable link and the other fork 52 toinsert the other pin 31 contained in its tines in the then alignedapertures of the other end of the cable link 36 and thefilled bucketcoupling arm 16.

When the cable is now raised, the cable link is rotated so that its newbucket arm-link connection extends downwardly, and the filled bucket arm16 rotates upwardly, both link member 36 and arm member 16 pivoting sothat the full bucket arm and the cable link are vertically extending insimilar orientation to that shown in FIG. 2, and as shown in FIG. 8.When the cable link 36 assumes a vertical position, the downwardlyextending arcuate plates 44 enter the grooves 46 at each end of thecoupling pins 31 so that the coupling pin 31 is held in positioncoupling the bucket arm 16 to the crane link 36. The empty and justlowered bucket in the bucket means is now available for filling.

It will be obvious, although not shown, that the micro-switch 50 whichdisconnected one bucket and connected the other may be used to causeautomatic switching of the cement feeding chute to switch a chute suchas the one shown from a feed position over the now full bucket to oneover the now empty bucket, without the necessity of performing suchchange manually.

FIG. shows a chute 41 operable between two positions by a cylinder 43 toalternate the two bucket locations, as shown in FIG. 1. As alreadystated, such an arrangement may, like the slide, be controlled by themicro-switch 50.

There are two principal aspects of the bucket described in the specificembodiment.

In one aspect of the bucket, this must be designed for cooperation withthe bucket holder previously described. Thus the bucket must be designedto rest on the holder, must be designed to cooperate with the holder toassume a predetermined orientation when lowered to rest therein and mustbe provided with coupling means for coupling to the crane cable.

In a second aspect, there is preferably provided a bucket suitable foruse with the bucket holder and satisfying the above criteria but, inaddition, providing a bucket with or without the above cooperatingaspects which allow the bucket bottom to be conveniently opened andclosed for dumping therethrough, and uses hydraulic instead of manualpower for this purpose (in distinction from present bottom openingbuckets) but does not require an exterior power source.

In the first aspect above discussed, the bucket is exteriorly shaped tobe easily received in the holder. In the present form the shaping of thebucket is as a surface of revolution open at the top, normally closed atthe bottom, with side walls cylindrical at the upper portion and withside walls forming a tapering cone from that portion downwardly to thebottom of the bucket.

As previously explained, cooperating means are required between theholder and the bucket to provide for coupling to the crane cable and inthis aspect, the holder provides the tracks 28 and to complement thesetracks the bucket is provided with diametrically opposed rollers 15which ride on the track and carry the bucket to the correct orientation.It will be obvious that there are alternative means ,of providingthrough cooperation of the bucket and the holder, that the bucket shallarrive at the correct orientation and that this may involve sliding ofthe bucket on the surface without rollers and may involve other sorts ofguideways and keying all in accord with techniques, well known to thoseskilled in the art, to achieve the correct orientation.

The bucket is, asalready described, provided with suspension means,designed with regard to the orientation achieved by the rollers on theguideways, to provide that when a lowered bucket has come to rest in theholder, in the proper location and orientation, it is uncoupled from thecrane cable and another bucket already resting in the holder, coupledthereto.

The bucket is preferably provided with bottom opening means, since thisis most suitable for cooperation with the bucket holder just described.

There is preferably provided a bottom opening bucket hydraulicallyactuated as hereinafter described. The principal of the operation ofhydraulically actuated opening for a suspended container, hereindiscussed, is not limited to crane buckets, but it is felt, may beapplied to any suspended container.

The schematic representation of FIGS. 12-14 may render the principle ofthe bottom opening bucket more understandable. The schematics may berelated to FIG. 3 with the cable connectable through the apparatusalready described (arm 16 and shank 40) to the piston 1 10 of actuatingcylinder 100. The actuating cylinder is connected as indicated in FIGS.3 and 1 to the frame of the crane bucket. The bottom closure cone 134for the bucket, is connectedto the piston 132, while the cylinder 130 isconnected to the frame of the bucket. The cylinders 130 and 100 and thelines connecting them will be filled with hydraulic fluid. As shown inthe drawings, a pair of lines 120 and 122 connect the opposite side ofthe actuating cylinder 100 to a control valve 124. The control valve 124is connected to an actuating device, here a hydraulic cylinder 130,through a pair of lines 126 and 128. As shown, with hydraulic cylinder100 attached to the bucket and the piston attached to the crane cable,the weight of the bucket on the cable tends to cause flow outward fromthe cylinder 100 along line above the piston and flow inward to thecylinder along line 122 below the piston. The effect of this tendency toflow is controlled by the control valve 124 operable, in the position ofFIG. 12 to direct hydraulic fluid to close the bucket by sending fluidalong line 126 toward cylinder and receiving fluid along line 128 fromcylinder 130; and in the position of FIG. 13 to open the bucket byreversing the connection between lines 120 and 122 on the one hand andlines 126 and 128 on the other hand and; in the position as shown inFIG. 14, to disconnect the actuating cylinder 100 from the actuablecylinder 130 and hence to prevent flow in lines 120 and 122. The onewayvalves in lines 120 and 122 labelled 131 and 132 respectively, allowflow only outwardly from cylinder 100 in line 120 and toward thecylinder in line 122. A line 130 also connects the upper side of theactuating cylinder 100 with the lower side'and this is provided with aone-way valve 133 allowing flow only from the lower side of the cylinder100 to the upper.

In the operation of suspending the bucket the location of these membersis shown in FIG. 12. Thus the bottom is closed and flow is prevented inlines 120 and 122 because the tendency for flow in these lines, in thedirection indicated by the arrows, holds closed the cone 134 against thecone 12 since the piston is moved to its lowest position as set bycontact of the cones l2 and 134.

In the lifting and lowering of the bucket into the holder (with thebucket arm suspended from the cable in distinction to FIG. 3) the bottom134 will thus be maintained closed for filling andcarrying concrete.When, with the bucket suspended by the cable, it is desired to dump thebucket, then the valve is shifted to the position of FIG. 13 so that theweight of the bucket pulls the piston 110 upward relative to thecylinder 100, the piston directs hydraulic fluid along the upper line120 into the lower end of the actuable cylinder 1311 to raise theactuating piston 132 while fluid flows out of the upper end of cylinderback to the actuating piston along lines 126, valve 124 and line 122.The raising of the actuating cylinder 132 raises the cone 134 relativeto the cone 12 opening the bottom of the bucket to dump the load. Whenthe load has been dumped in this manner and it is desired to close thebucket, the manual control is set to set the valve in the position ofFIG. 12. The flow of fluid from the upper end of the actuating cylinder100 under the weight of the bucket is still actuated by the weight ofthe bucket, to pump hyl draulic fluid through line 120, the controlvalve 124 and to the upper end of the actuable cylinder 130 to lower thepiston 132 and the closure member 134 until it closes the bottom of thebucket by contacting cone 12 and at the same time stopping hydraulicflow. During closing of the bucket and lowering of the piston 132,return flow from the actuable cylinder 130 takes place through line 128and line 122.

The piston 100 is returned to its lowest position under the weight ofthe rod 40 and the piston 110 when the piston is not suspended but isresting in the bucket holder. In this position, the hydraulic operationis, as is demonstrated in FIG. 14. In this position the weight of therod 40 and piston 132 will tend to move the piston 110 downwardly in thecylinder 100. In the preferred embodiment, positive force is added tothe gravitational by providing a compression spring 111 bearingdownwardly on a shoulder movable with rod 40 and upwardly on a shoulderattached to the bucket frame and designed to bias rod 40 and piston 110downwardly relative to bucket and cylinder 100. (In the preferredembodiment the rod 40 is connected to the actual piston rod of piston110 through a pivot 113 to prevent transmission of the suspensionstresses from rod 40 to the piston rod and downward stresses between therod 40 and the piston rod are effectively transmitted through the pivot113.) With piston 110 moving downwardly relative to cylinder 100 fluidis forced outwardly through line 122 and drawn inwardly along line 120.Since the outward flow'along line 122 is blocked by valve 132 and inwardflow along line 120 cannot take place through valve 131, the flow takesplace from the lower to the upper side of the piston along line 122,

valve 133, line 130 and line 120. The piston 110 is thereforemoveddownwardly in its cylinder and the fluid fills the spacethereabove, ready to actuate the opening and closing of the bottom ofthe bucket when the cylinder is again suspended. If the piston 110cannot be sufficiently lowered to actuate these operations during theintervals in which the bucket is supported in the holder, this intervalmay be lengthened from time to time on the bucket set on another surfacesufficiently long to sufficiently lower the piston 132 in the cylinder130.

Some generalizing aspects of the opening and closingv apparatus shouldbe noted. The principle is a hydraulic means for usingthe weight of asuspended article to provide the hydraulic pressure for opening andclosing the suspended container. It is noted, therefore, that it isnot-necessary to the invention that the container be a cement bucketalthough the invention is admirably suited for this purpose.

It is further noted that the invention is not limited to the type ofbottom opening using the member 134 shown, since the hydraulic forcedeveloped by the suspended container may be used to provide otheropening and closure means. Such other opening and closure means couldinclude using the hydraulic force developed by a suspended container tomove a horizontal slide for a bottom opening container (as now performedmanually) or using the hydraulic force developed for a side opening forthe container.

I claim:

1. Hydraulic opening means for a container normally suspendedcomprising:

an actuating hydraulic cylinder;

an actuable reversible hydraulic device connected to control the openingand closing of said container,

a pair of hydraulic lines connecting the hydraulic cylinder on oppositesides of the piston therein to a control valve and a pair of hydrauliclines connecting the control valve to the hydraulically actuable device,

said control valve being designed to connect said hydraulic cylinder tosaid device in one sense or in the reverse sense, or to disconnect saidhydraulic cylinder from said device. said container opening controlbeing designed so that flow to said actuable device in one sense causesopening of said container and flow to said actuable device in the othersense causes closing of said container. said actuating hydrauliccylinder being connected to form part of the mechanical connectionbetween said container and the suspension means therefor, saidconnection being designed and constructed so that the weight of thesuspended container tends to move the actuating piston and cylinderrelative to one another to tend to move hydraulic fluid in said lines.

whereby: with the; control means disconnecting the actuating and theactuable devices, the container may, while suspended, be maintained inits closed or open states; with the control means connecting theactuating and actuable device in one sense, and

- the device suspended by the suspension means, the

actuable device opens the container; with the control means connectingthe actuating and actuable device in the other sense the actuable devicecloses the container.

2. A device as claimed in claim 1 wherein the hydraulic actuating deviceis also mechanically and hydraulically connected so that the containeron a base surface tends to move the piston relative to the cylinder inan opposite direction to the tendency for relative moveto create forcestending, when said bucket is suspended thereby from a cable, to move afirst piston in one direction relative to a first hydraulic cylinder,

said controlled opening and closing means for the bottom of said bucketbeing designed and constructed to be operated in accord with relativemovement between a second piston and a second hydraulic cylinder,

connections for providing a supply of hydraulic fluid under pressure dueto relative movement in one direction of said first piston relative tosaid first cylinder to cause movement of said second piston relative tosaid second cylinder,

a valve having at least two settings for controlling said connections,said two settings corresponding to:

a. hydraulic flow between said firstand said second cylinder in ahydraulic connection such that movement of said first piston relative tosaid first cylinder due to the weight of said bucket on said cablecauses flow to said second cylinder in a direction to cause increasedopening of the bottom of said bucket, i

b. hydraulic flow between said first and said second cylinder in ahydraulic connection such that movement of said first piston relative tosaid first cylinder due to the weight of said bucket on said cablecauses flow to said second cylinder in a direction to cause decreasedopening of the bottom of said bucket.

4. Apparatus as claimed in claim 3 wherein said bucket, first piston andcylinder are designed so that said bucket resting with its own weight ona supporting surface is designed to create forces tending, when saidbucket is suspended thereby from a cable, to move said first piston inthe'other direction relative to said first hydraulic cylinder,

an hydraulic line connects said first cylinder on one side of said firstpiston with said first cylinder on the other side of said first piston,

said last-mentioned line being provided with a one way valve meansallowing flow in said line only when said piston movement relative tosaid operative cylinder is in said other direction.

5. Means as claimed in claim 3 including means for preventing flow fromsaid first cylinder to said valve when said first piston movementrelative to said first cylinder is in said other direction.

1. Hydraulic opening means for a container normally suspendedcomprising: an actuating hydraulic cylinder; an actuable reversiblehydraulic device connected to control the opening and closing of saidcontainer, a pair of hydraulic lines connecting the hydraulic cylinderon opposite sides of the piston therein to a control valve and a pair ofhydraulic lines connecting the control valve to the hydraulicallyactuable device, said control valve being designed to connect saidhydraulic cylinder to said device in one sense or in the reverse sense,or to disconnect said hydraulic cylinder from said device. saidcontainer opening control being designed so that flow to said actuabledevice in one sense causes opening of said container and flow to saidactuable device in the other sense causes closing of said container.said actuating hydraulic cylinder being connected to form part of themechanical connection between said container and the suspension meanstherefor, said connection being designed and constructed so that theweight of the suspended container tends to move the actuating piston andcylinder relative to one another to tend to move hydraulic fluid in saidlines. whereby: with the control means disconnecting the actuating andthe actuable devices, the container may, while suspended, be maintainedin its closed or open states; with the control means connecting theactuating and actuable device in one sense, and the device suspended bythe suspension means, the actuable device opens the container; with thecontrol means connecting the actuating and actuable device in the othersense the actuable device closes the container.
 2. A device as claimedin claim 1 wherein the hydraulic actuating device is also mechanicallyand hydraulically connected so that the container on a base surfacetends to move the piston relative to the cylinder in an oppositedirection to the tendency for relative movement when said container issuspended. a line connecting the actuating cylinder on one side of saidpiston with the actuating cylinder on the other side of said piston,said last-mentioned line being provided with one way valve meansallowing flow in said line only when said piston movement relative tosaid operating cylinder is in said opposite direction.
 3. A bucket, anupper connection to allow said bucket to be suspended by a crane cable,a controlled opening and clOsing means for the bottom of said bucket,the suspension means for said bucket being designed to create forcestending, when said bucket is suspended thereby from a cable, to move afirst piston in one direction relative to a first hydraulic cylinder,said controlled opening and closing means for the bottom of said bucketbeing designed and constructed to be operated in accord with relativemovement between a second piston and a second hydraulic cylinder,connections for providing a supply of hydraulic fluid under pressure dueto relative movement in one direction of said first piston relative tosaid first cylinder to cause movement of said second piston relative tosaid second cylinder, a valve having at least two settings forcontrolling said connections, said two settings corresponding to: a.hydraulic flow between said first and said second cylinder in ahydraulic connection such that movement of said first piston relative tosaid first cylinder due to the weight of said bucket on said cablecauses flow to said second cylinder in a direction to cause increasedopening of the bottom of said bucket, b. hydraulic flow between saidfirst and said second cylinder in a hydraulic connection such thatmovement of said first piston relative to said first cylinder due to theweight of said bucket on said cable causes flow to said second cylinderin a direction to cause decreased opening of the bottom of said bucket.4. Apparatus as claimed in claim 3 wherein said bucket, first piston andcylinder are designed so that said bucket resting with its own weight ona supporting surface is designed to create forces tending, when saidbucket is suspended thereby from a cable, to move said first piston inthe other direction relative to said first hydraulic cylinder, anhydraulic line connects said first cylinder on one side of said firstpiston with said first cylinder on the other side of said first piston,said last-mentioned line being provided with a one way valve meansallowing flow in said line only when said piston movement relative tosaid operative cylinder is in said other direction.
 5. Means as claimedin claim 3 including means for preventing flow from said first cylinderto said valve when said first piston movement relative to said firstcylinder is in said other direction.